Best "short notice" advice is "Plan Ahead"!

Reference checking has become quite prevalent in the SF Bay Area and I'd guess in many other locales as well, and "short notice" has become correspondingly more difficult - at least with ladies that I'd personally consider high quality.  (I know this - I get impulsive occasionally also - lol.)

Your query about a "nice lady" is a bit too vague - in future, you'd do well to provide more specifics (even if your "specifics" comprise a wide range.)

Arguably, the easiest might be AAMP girls (google "aamp escort" if you're unfamiliar with the acronym.)  (Personally, though I've indulged and enjoyed AAMP in the past, I ain't into that scene any more.)

Alternatively, there are some agencies such as Playmateconnections who will do alternative reference checking with some personal information if you're comfortable with that.